nut-cutting time

The point when you have tried everything but failed.

While the “nut-cutting time” originally refers to the effort required to remove a rusted or stripped nut, it has come to be used in a legislative context as the time to exert maximum effort to round up votes to get a bill passed due to an approaching deadline.

While the term did not originally refer to castration, many have used that as its double-meaning in a political context.